Monitoring system

Abstract

The monitoring system includes: locators that each have an arm moved by a motor and align, at the respective positions, a workpiece conveyed to a work area; and a monitoring device that calculates a comparison value for each of the locators by comparing a current value supplied to the motor with a representative value set for each of the locators and associated with the current value.

What is claimed is: 
     
         1 . A monitoring system comprising:
 locators that each have an arm moved by a motor and align, at the respective positions, a workpiece conveyed to a work area; and   a monitoring device that calculates a comparison value for each of the locators by comparing a current value supplied to the motor with a representative value set for each of the locators and associated with the current value.   
     
     
         2 . The monitoring system of  claim 1 , wherein
 the representative value is the current value when a master workpiece is aligned.   
     
     
         3 . The monitoring system of  claim 1 , wherein
 the workpiece comprises workpieces, and the representative value is an average value of the current values when the workpieces in the same type are aligned.   
     
     
         4 . The monitoring system of  claim 1 , wherein
 the representative value is one current value selected from the current values for the respective locators supplied at the same timing.   
     
     
         5 . The monitoring system of  claim 1 , wherein
 the arm supports the workpiece from below,   the motor moves the arm in an up-down direction, and   the monitoring device acquires the current value when the arm supports the workpiece.   
     
     
         6 . The monitoring system of  claim 5 , wherein
 the locators support the workpiece conveyed to the work area by a carrier while a robot is in operation on the workpiece.   
     
     
         7 . The monitoring system of  claim 1 , further comprising:
 a display device that displays the comparison value calculated by the monitoring device for each of the locators in the same arrangement as that of the locators.